Vernonia plant named ‘Summer&#39;s Surrender’

ABSTRACT

A new cultivar of  Vernonia  plant, ‘Summer&#39;s Surrender’, that is characterized by its bushy upright plant habit with stems that do not lodge, its plant habit that is distinctly more wide than tall, its foliage that is darker green in color, its resistance to rust and powdery mildew, in being reliably hardy in U.S.D.A. Zones 4 to 9 and in being very drought tolerant.

Botanical classification: Vernonia hybrid.

Variety denomination: ‘Summer's Surrender’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Vernoniaplant of hybrid origin and will be referred to hereinafter by itscultivar name, ‘Summer's Surrender’. The new cultivar represents a newherbaceous perennial grown for landscape use.

The new invention arose from an ongoing breeding program by the Inventorin Glencoe, Ill. The objectives of the breeding program are to developimproved cultivars of interspecific hybrids of Vernonia with novelornamental traits such as plant habit, disease resistance, hardiness inU.S.D.A. Zone 5 and in ground cultural adaptability.

‘Summer's Surrender’ was derived from a cross made in September of 2010under controlled conditions between unnamed unpatented plants ofVernonia lettermannii as the female seed parent and an unnamed andunpatented plant of Vernonia arkansana as the male pollen parent.‘Summer's Surrender’ was selected in September of 2013 as a singleunique plant amongst the resulting seedlings.

Asexual propagation of the new cultivar was first accomplished by shoottip cuttings by the Inventor in June 2013 in Glencoe, Ill. Asexualpropagation by shoot tip cuttings has determined that thecharacteristics of this cultivar are stable and reproduced true to typein successive generations.

SUMMARY OF THE INVENTION

The following traits have been repeatedly observed and represent thecharacteristics of the new cultivar. These attributes in combinationdistinguish ‘Summer's Surrender’ as a new and unique cultivar ofVernonia.

-   1. ‘Summer's Surrender’ exhibits a bushy upright plant habit with    stems that do not lodge.-   2. ‘Summer's Surrender’ exhibits a plant habit that is distinctly    more wide than tall.-   3. ‘Summer's Surrender’ exhibits foliage that is darker green in    color.-   4. ‘Summer's Surrender’ exhibits resistance to rust and powdery    mildew.-   5. ‘Summer's Surrender’ is reliably hardy in U.S.D.A. Zones 4 to 9.-   6. ‘Summer's Surrender’ is very drought tolerant.

The female parent, an unnamed plant of Vernonia lettermannii, differsfrom ‘Summer's Surrender’ in having a plant size that is smaller inheight and width, in having stems that have shown lodging and in havingfewer florets per capitulum. The male parent, Vernonia arkansana,differs from ‘Summer's Surrender’ in having phyllaries that are shorterin length with long tapered tips that are incurved and held away fromthe capitulum base, in having more florets per capitulum, in havingsusceptibility to rust and in having leaves that are longer and wider inmeasurement and are densely covered with pubescence across the abaxialsurfaces. ‘Summer's Surrender’ can also be compared to the cultivarVernonia lettermannii ‘Iron Butterfly’ (not patented) and Vernonia‘Southern Cross’ (not patented). ‘Iron Butterfly’ is similar to‘Summer's Surrender’ in having a bushy, broad plant habit, in havingstems that do not lodge and in having a high resistance to powderymildew and rust. ‘Iron Butterfly’ differs from ‘Summer's Surrender’ inhaving fewer florets per capitulum, in having leaves that are smaller insize with margins that are entire and in having a plant size that issmaller in height and width. ‘Southern Cross’ is similar to ‘Summer'sSurrender’ in having a similar leaf shape, margins and size and inhaving the same resistance to lodging. ‘Southern Cross’ differs from‘Summer's Surrender’ in having a plant habit that is more narrow inshape, in having a plant size that is smaller in height and width, inbeing susceptible to rust and in producing fewer florets per capitulum.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying colored photographs illustrate the overall appearanceand distinct characteristics of the new Vernonia. The photographs weretaken of ‘Summer's Surrender’ as grown in a trial garden in Glencoe,Ill.

The photograph in FIG. 1 provides a top view of a 3 year-old plant of‘Summer's Surrender’ in bloom.

The photograph in FIG. 2 provides a close up view of the foliage andflowers of a 5 year-old plant of ‘Summer's Surrender’.

The photograph in FIG. 3 provides a close up view of the foliage andflowers of a 3 year-old plant of ‘Summer's Surrender’.

The colors in the photographs are as close as possible with thephotographic and printing technology utilized and the color values citedin the Detailed Botanical Description accurately describe the colors ofthe new Vernonia.

DETAILED BOTANICAL DESCRIPTION

The following is a detailed description of three year-old plants of thenew cultivar as grown outdoors in a trial plot in Glencoe, Ill. Thephenotype of the new cultivar may vary with variations in environmental,climatic, and cultural conditions, as it has not been tested under allpossible environmental conditions. The color determination is inaccordance with The 2015 R.H.S. Colour Chart of The Royal HorticulturalSociety, London, England, except where general color terms of ordinarydictionary significance are used.

-   General description:    -   -   Blooming period.—Four to five weeks from early September to            early October in northern Illinois.        -   Plant type.—Herbaceous Perennial.        -   Plant habit.—Bushy upright plant habit with stems that do            not lodge.        -   Height and spread.—In-ground trial plants 3 years in age;            123 cm in height and 210 cm in width at peak bloom,            in-ground trial plants 5 years in age; 125 cm in height and            190 cm in width at peak bloom.        -   Hardiness.—At least hardy in U.S.D.A. Zone 4 to 9.        -   Diseases.—Highly resistant to powdery mildew and rust.        -   Root description.—Fibrous, 155A in color.        -   Propagation.—Shoot tip cuttings.        -   Growth rate.—Vigorous.        -   Root development.—Shoot tip cuttings will root under mist in            4 to 5 weeks in late spring to early summer, rooted cutting            will fully root in a 2.5 inch pot in about two months and            when transplanted in fall and overwintered in a 4.5 inch            pot, they will bloom the following spring.-   Stem description:    -   -   Shape.—Main branch; round, lateral branches oval to round.        -   Stem color.—Main branch; a blend of 145A, 141A and 144D,            leaf scars 200A, lateral branches; a blend of 145A, 141A and            144D.        -   Stem size.—Main branches; average of 99.5 cm in length and            an average of 5 mm in diameter, lateral branches; average of            15 cm in length and an average of 2 mm in width.        -   Stem surface.—Glossy, smooth and ridged, leaf scars are            present and an average of 2 scars per linear cm.        -   Branching number.—An average of 120 main branches, an            average of 15 lateral branches per main branch.        -   Branching habit.—Main branches occur from the base held at            straight upright vertical angle, lateral branches held at a            65° angle (90°=vertical), very strong.-   Foliage description:    -   -   Leaf division.—Simple.        -   Leaf arrangement.—Alternate, sometimes opposite.        -   Leaf shape.—Linear.        -   Leaf size.—Up to 12 cm in length and 4 mm in width.        -   Leaf number.—Average of 75 per main branch and 21 per            lateral branch.        -   Leaf base.—Acute.        -   Leaf apex.—Acute.        -   Leaf margin.—Finely denticulate, teeth spread an average of            4 mm apart and color of teeth is 151A in color, the entire            space between matches leaf color.        -   Leaf venation.—Pinnate, one main middle vein, upper and            lower surface color; base of vein to a quarter up is N144A,            remaining vein to tip matches leaf color.        -   Leaf surface.—Both surfaces glabrous and dull.        -   Internode length.—Main branch up to 2 cm, lateral branches            up to 4 cm.        -   Leaf color.—Young and mature upper and lower surfaces; 146A.        -   Leaf attachment.—Sessile.        -   Petioles.—No petioles, leaves growing directly from the            stem, also growing underneath lateral branches.-   Inflorescence description:    -   -   Inflorescence type.—Corymb.        -   Inflorescence number.—1 per stem.        -   Inflorescence fragrance.—None.        -   Inflorescence size.—Average of 30 cm in depth and 28 cm in            diameter.        -   Peduncles.—Oval in shape, up to 3 cm in length and 2 mm in            diameter, surface is dull, ridged and glabrous, color is a            blend of 145A, 141A and 144D.        -   Pedicels.—Oval in shape and up to 2 cm in length and 1 mm in            diameter, surface is dull, ridged and glabrous, color is a            blend of 145A, 141A and 144D.        -   Phyllaries.—About 50 per capitulum, discoid head, acute            tips, entire margins, bluntly acute base, smaller phyllaries            linear in shape, up to 3 mm in length and 1 mm in width,            color of outer and inner surfaces; tip is N92A, remaining            surfaces 144A in color, larger phyllaries lanceolate in            shape average of 7 mm in length and 1 mm in width, color of            outer and inner surfaces; tip to mid section and margins a            blend of 59A and 60B, mid section to base 196A.        -   Floret buds.—Linear in shape, average of 5 mm in length and            1 mm in width, color; base 155A, mid section a blend of N82C            and N80A, tip 79A.        -   Flower longevity.—Average of 3 to 5 days per floret,            depending on temperature.        -   Floret type.—Discoid florets, no ray florets.        -   Floret quantity.—Average of 28 per capitulum.        -   Floret.—Just before floral anthesis; 1 cm in depth, 5 mm in            width, elongated tube in shape and flat on top, base a blend            of 138A, and 146A, mid section a blend of 138A and N92A, tip            is a blend of N92A and 158A, when open; average of 1 cm in            diameter and 1.5 cm in depth, base a blend of 143A and 142B,            mid section a blend of N92A, and N79A, tip is a blend of            N81A, 164B, 165A, N187A and NN155A.        -   Petals.—5 petals, 50% of petals fused, free top portion;            base to mid section is linear in shape, un-fused portion of            petals drop into downward and inward hanging angles and            slightly curl under, tube is 5 mm in length and 1 mm in            width, loose petals at top are 3 mm in length and 0.5 mm in            width, petal tips acute in shape, inner and outer surfaces            are glabrous and slightly velvety, entire margins, base            fused to tube, color; inner and outer surfaces; base and mid            section 83B, tips 83A.        -   Pistils.—1 per floret, bi-fid stigma, 86A in color, 2 mm in            length and 3 mm in width, style 1 cm in length and <0.5 mm            in width, a blend of 86A and NN155B in color, ovary is 2 mm            in length and 1 mm in width and oval in shape, NN155A in            color, pappus bristles at base, 6 mm in length, color            ranging between NN155A and 86C.        -   Stamens.—1 per floret, 4 filaments very fine, 5 mm in            length, translucent, close to NN155B in color, 2 anthers, 4            mm in length and 2 mm in width, NN155A, tip 86A, moderate            amount of pollen observed when first blooming; NN155A in            color.        -   Fruit/seeds.—Fruit and seed production was not observed to            date.

It is claimed:
 1. A new and distinct variety of Vernonia plantdesignated ‘Summer's Surrender’ as described and illustrated herein.